<?php

if (! defined('BASEPATH'))
    exit('No direct script access allowed');

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package CodeIgniter
 * @author Esen Sagynov
 * @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license http://codeigniter.com/user_guide/license.html
 * @link http://codeigniter.com
 * @since Version 2.0.2
 * @filesource
 *
 */
    
// ------------------------------------------------------------------------

/**
 * CUBRID Database Adapter Class
 *
 * Note: _DB is an extender class that the app controller
 * creates dynamically based on whether the active record
 * class is being used or not.
 *
 * @package CodeIgniter
 * @subpackage Drivers
 * @category Database
 * @author Esen Sagynov
 * @link http://codeigniter.com/user_guide/database/
 */
class CI_DB_cubrid_driver extends CI_DB
{
    
    // Default CUBRID Broker port. Will be used unless user
    // explicitly specifies another one.
    const DEFAULT_PORT = 33000;

    var $dbdriver = 'cubrid';
    
    // The character used for escaping - no need in CUBRID
    var $_escape_char = '';
    
    // clause and character used for LIKE escape sequences - not used in CUBRID
    var $_like_escape_str = '';

    var $_like_escape_chr = '';

    /**
     * The syntax to count rows is slightly different across different
     * database engines, so this string appears in each driver and is
     * used for the count_all() and count_all_results() functions.
     */
    var $_count_string = 'SELECT COUNT(*) AS ';

    var $_random_keyword = ' RAND()';
 // database specific random keyword
    
    /**
     * Non-persistent database connection
     *
     * @access private called by the base class
     * @return resource
     */
    function db_connect ()
    {
        // If no port is defined by the user, use the default value
        if ($this->port == '') {
            $this->port = self::DEFAULT_PORT;
        }
        
        $conn = cubrid_connect($this->hostname, $this->port, $this->database, 
                $this->username, $this->password);
        
        if ($conn) {
            // Check if a user wants to run queries in dry, i.e. run the
            // queries but not commit them.
            if (isset($this->auto_commit) && ! $this->auto_commit) {
                cubrid_set_autocommit($conn, CUBRID_AUTOCOMMIT_FALSE);
            } else {
                cubrid_set_autocommit($conn, CUBRID_AUTOCOMMIT_TRUE);
                $this->auto_commit = TRUE;
            }
        }
        
        return $conn;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Persistent database connection
     * In CUBRID persistent DB connection is supported natively in CUBRID
     * engine which can be configured in the CUBRID Broker configuration
     * file by setting the CCI_PCONNECT parameter to ON.
     * In that case, all
     * connections established between the client application and the
     * server will become persistent. This is calling the same
     * @cubrid_connect function will establish persisten connection
     * considering that the CCI_PCONNECT is ON.
     *
     * @access private called by the base class
     * @return resource
     */
    function db_pconnect ()
    {
        return $this->db_connect();
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Reconnect
     *
     * Keep / reestablish the db connection if no queries have been
     * sent for a length of time exceeding the server's idle timeout
     *
     * @access public
     * @return void
     */
    function reconnect ()
    {
        if (cubrid_ping($this->conn_id) === FALSE) {
            $this->conn_id = FALSE;
        }
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Select the database
     *
     * @access private called by the base class
     * @return resource
     */
    function db_select ()
    {
        // In CUBRID there is no need to select a database as the database
        // is chosen at the connection time.
        // So, to determine if the database is "selected", all we have to
        // do is ping the server and return that value.
        return cubrid_ping($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Set client character set
     *
     * @access public
     * @param
     *            string
     * @param
     *            string
     * @return resource
     */
    function db_set_charset ($charset, $collation)
    {
        // In CUBRID, there is no need to set charset or collation.
        // This is why returning true will allow the application continue
        // its normal process.
        return TRUE;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Version number query string
     *
     * @access public
     * @return string
     */
    function _version ()
    {
        // To obtain the CUBRID Server version, no need to run the SQL query.
        // CUBRID PHP API provides a function to determin this value.
        // This is why we also need to add 'cubrid' value to the list of
        // $driver_version_exceptions array in DB_driver class in
        // version() function.
        return cubrid_get_server_info($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Execute the query
     *
     * @access private called by the base class
     * @param
     *            string an SQL query
     * @return resource
     */
    function _execute ($sql)
    {
        $sql = $this->_prep_query($sql);
        return @cubrid_query($sql, $this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Prep the query
     *
     * If needed, each database adapter can prep the query string
     *
     * @access private called by execute()
     * @param
     *            string an SQL query
     * @return string
     */
    function _prep_query ($sql)
    {
        // No need to prepare
        return $sql;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Begin Transaction
     *
     * @access public
     * @return bool
     */
    function trans_begin ($test_mode = FALSE)
    {
        if (! $this->trans_enabled) {
            return TRUE;
        }
        
        // When transactions are nested we only begin/commit/rollback the
        // outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }
        
        // Reset the transaction failure flag.
        // If the $test_mode flag is set to TRUE transactions will be rolled
        // back
        // even if the queries produce a successful result.
        $this->_trans_failure = ($test_mode === TRUE) ? TRUE : FALSE;
        
        if (cubrid_get_autocommit($this->conn_id)) {
            cubrid_set_autocommit($this->conn_id, CUBRID_AUTOCOMMIT_FALSE);
        }
        
        return TRUE;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Commit Transaction
     *
     * @access public
     * @return bool
     */
    function trans_commit ()
    {
        if (! $this->trans_enabled) {
            return TRUE;
        }
        
        // When transactions are nested we only begin/commit/rollback the
        // outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }
        
        cubrid_commit($this->conn_id);
        
        if ($this->auto_commit && ! cubrid_get_autocommit($this->conn_id)) {
            cubrid_set_autocommit($this->conn_id, CUBRID_AUTOCOMMIT_TRUE);
        }
        
        return TRUE;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Rollback Transaction
     *
     * @access public
     * @return bool
     */
    function trans_rollback ()
    {
        if (! $this->trans_enabled) {
            return TRUE;
        }
        
        // When transactions are nested we only begin/commit/rollback the
        // outermost ones
        if ($this->_trans_depth > 0) {
            return TRUE;
        }
        
        cubrid_rollback($this->conn_id);
        
        if ($this->auto_commit && ! cubrid_get_autocommit($this->conn_id)) {
            cubrid_set_autocommit($this->conn_id, CUBRID_AUTOCOMMIT_TRUE);
        }
        
        return TRUE;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Escape String
     *
     * @access public
     * @param
     *            string
     * @param
     *            bool whether or not the string will be used in a LIKE
     *            condition
     * @return string
     */
    function escape_str ($str, $like = FALSE)
    {
        if (is_array($str)) {
            foreach ($str as $key => $val) {
                $str[$key] = $this->escape_str($val, $like);
            }
            
            return $str;
        }
        
        if (function_exists('cubrid_real_escape_string') and
                 is_resource($this->conn_id)) {
            $str = cubrid_real_escape_string($str, $this->conn_id);
        } else {
            $str = addslashes($str);
        }
        
        // escape LIKE condition wildcards
        if ($like === TRUE) {
            $str = str_replace(array(
                    '%',
                    '_'
            ), array(
                    '\\%',
                    '\\_'
            ), $str);
        }
        
        return $str;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Affected Rows
     *
     * @access public
     * @return integer
     */
    function affected_rows ()
    {
        return @cubrid_affected_rows($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Insert ID
     *
     * @access public
     * @return integer
     */
    function insert_id ()
    {
        return @cubrid_insert_id($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * "Count All" query
     *
     * Generates a platform-specific query string that counts all records in
     * the specified table
     *
     * @access public
     * @param
     *            string
     * @return string
     */
    function count_all ($table = '')
    {
        if ($table == '') {
            return 0;
        }
        
        $query = $this->query(
                $this->_count_string . $this->_protect_identifiers('numrows') .
                         " FROM " .
                         $this->_protect_identifiers($table, TRUE, NULL, FALSE));
        
        if ($query->num_rows() == 0) {
            return 0;
        }
        
        $row = $query->row();
        $this->_reset_select();
        return (int) $row->numrows;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * List table query
     *
     * Generates a platform-specific query string so that the table names can be
     * fetched
     *
     * @access private
     * @param
     *            boolean
     * @return string
     */
    function _list_tables ($prefix_limit = FALSE)
    {
        $sql = "SHOW TABLES";
        
        if ($prefix_limit !== FALSE and $this->dbprefix != '') {
            $sql .= " LIKE '" . $this->escape_like_str($this->dbprefix) . "%'";
        }
        
        return $sql;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Show column query
     *
     * Generates a platform-specific query string so that the column names can
     * be fetched
     *
     * @access public
     * @param
     *            string the table name
     * @return string
     */
    function _list_columns ($table = '')
    {
        return "SHOW COLUMNS FROM " .
                 $this->_protect_identifiers($table, TRUE, NULL, FALSE);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Field data query
     *
     * Generates a platform-specific query so that the column data can be
     * retrieved
     *
     * @access public
     * @param
     *            string the table name
     * @return object
     */
    function _field_data ($table)
    {
        return "SELECT * FROM " . $table . " LIMIT 1";
    }
    
    // --------------------------------------------------------------------
    
    /**
     * The error message string
     *
     * @access private
     * @return string
     */
    function _error_message ()
    {
        return cubrid_error($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * The error message number
     *
     * @access private
     * @return integer
     */
    function _error_number ()
    {
        return cubrid_errno($this->conn_id);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Escape the SQL Identifiers
     *
     * This function escapes column and table names
     *
     * @access private
     * @param
     *            string
     * @return string
     */
    function _escape_identifiers ($item)
    {
        if ($this->_escape_char == '') {
            return $item;
        }
        
        foreach ($this->_reserved_identifiers as $id) {
            if (strpos($item, '.' . $id) !== FALSE) {
                $str = $this->_escape_char .
                         str_replace('.', $this->_escape_char . '.', $item);
                
                // remove duplicates if the user already included the escape
                return preg_replace('/[' . $this->_escape_char . ']+/', 
                        $this->_escape_char, $str);
            }
        }
        
        if (strpos($item, '.') !== FALSE) {
            $str = $this->_escape_char .
                     str_replace('.', 
                            $this->_escape_char . '.' . $this->_escape_char, 
                            $item) . $this->_escape_char;
        } else {
            $str = $this->_escape_char . $item . $this->_escape_char;
        }
        
        // remove duplicates if the user already included the escape
        return preg_replace('/[' . $this->_escape_char . ']+/', 
                $this->_escape_char, $str);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * From Tables
     *
     * This function implicitly groups FROM tables so there is no confusion
     * about operator precedence in harmony with SQL standards
     *
     * @access public
     * @param
     *            type
     * @return type
     */
    function _from_tables ($tables)
    {
        if (! is_array($tables)) {
            $tables = array(
                    $tables
            );
        }
        
        return '(' . implode(', ', $tables) . ')';
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Insert statement
     *
     * Generates a platform-specific insert string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the insert keys
     * @param
     *            array the insert values
     * @return string
     */
    function _insert ($table, $keys, $values)
    {
        return "INSERT INTO " . $table . " (\"" . implode('", "', $keys) .
                 "\") VALUES (" . implode(', ', $values) . ")";
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Replace statement
     *
     * Generates a platform-specific replace string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the insert keys
     * @param
     *            array the insert values
     * @return string
     */
    function _replace ($table, $keys, $values)
    {
        return "REPLACE INTO " . $table . " (\"" . implode('", "', $keys) .
                 "\") VALUES (" . implode(', ', $values) . ")";
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Insert_batch statement
     *
     * Generates a platform-specific insert string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the insert keys
     * @param
     *            array the insert values
     * @return string
     */
    function _insert_batch ($table, $keys, $values)
    {
        return "INSERT INTO " . $table . " (\"" . implode('", "', $keys) .
                 "\") VALUES " . implode(', ', $values);
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Update statement
     *
     * Generates a platform-specific update string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the update data
     * @param
     *            array the where clause
     * @param
     *            array the orderby clause
     * @param
     *            array the limit clause
     * @return string
     */
    function _update ($table, $values, $where, $orderby = array(), $limit = FALSE)
    {
        foreach ($values as $key => $val) {
            $valstr[] = sprintf('"%s" = %s', $key, $val);
        }
        
        $limit = (! $limit) ? '' : ' LIMIT ' . $limit;
        
        $orderby = (count($orderby) >= 1) ? ' ORDER BY ' .
                 implode(", ", $orderby) : '';
        
        $sql = "UPDATE " . $table . " SET " . implode(', ', $valstr);
        
        $sql .= ($where != '' and count($where) >= 1) ? " WHERE " .
                 implode(" ", $where) : '';
        
        $sql .= $orderby . $limit;
        
        return $sql;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Update_Batch statement
     *
     * Generates a platform-specific batch update string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the update data
     * @param
     *            array the where clause
     * @return string
     */
    function _update_batch ($table, $values, $index, $where = NULL)
    {
        $ids = array();
        $where = ($where != '' and count($where) >= 1) ? implode(" ", $where) .
                 ' AND ' : '';
        
        foreach ($values as $key => $val) {
            $ids[] = $val[$index];
            
            foreach (array_keys($val) as $field) {
                if ($field != $index) {
                    $final[$field][] = 'WHEN ' . $index . ' = ' . $val[$index] .
                             ' THEN ' . $val[$field];
                }
            }
        }
        
        $sql = "UPDATE " . $table . " SET ";
        $cases = '';
        
        foreach ($final as $k => $v) {
            $cases .= $k . ' = CASE ' . "\n";
            foreach ($v as $row) {
                $cases .= $row . "\n";
            }
            
            $cases .= 'ELSE ' . $k . ' END, ';
        }
        
        $sql .= substr($cases, 0, - 2);
        
        $sql .= ' WHERE ' . $where . $index . ' IN (' . implode(',', $ids) . ')';
        
        return $sql;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Truncate statement
     *
     * Generates a platform-specific truncate string from the supplied data
     * If the database does not support the truncate() command
     * This function maps to "DELETE FROM table"
     *
     * @access public
     * @param
     *            string the table name
     * @return string
     */
    function _truncate ($table)
    {
        return "TRUNCATE " . $table;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Delete statement
     *
     * Generates a platform-specific delete string from the supplied data
     *
     * @access public
     * @param
     *            string the table name
     * @param
     *            array the where clause
     * @param
     *            string the limit clause
     * @return string
     */
    function _delete ($table, $where = array(), $like = array(), $limit = FALSE)
    {
        $conditions = '';
        
        if (count($where) > 0 or count($like) > 0) {
            $conditions = "\nWHERE ";
            $conditions .= implode("\n", $this->ar_where);
            
            if (count($where) > 0 && count($like) > 0) {
                $conditions .= " AND ";
            }
            $conditions .= implode("\n", $like);
        }
        
        $limit = (! $limit) ? '' : ' LIMIT ' . $limit;
        
        return "DELETE FROM " . $table . $conditions . $limit;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Limit string
     *
     * Generates a platform-specific LIMIT clause
     *
     * @access public
     * @param
     *            string the sql query string
     * @param
     *            integer the number of rows to limit the query to
     * @param
     *            integer the offset value
     * @return string
     */
    function _limit ($sql, $limit, $offset)
    {
        if ($offset == 0) {
            $offset = '';
        } else {
            $offset .= ", ";
        }
        
        return $sql . "LIMIT " . $offset . $limit;
    }
    
    // --------------------------------------------------------------------
    
    /**
     * Close DB Connection
     *
     * @access public
     * @param
     *            resource
     * @return void
     */
    function _close ($conn_id)
    {
        @cubrid_close($conn_id);
    }
}


/* End of file cubrid_driver.php */
/* Location: ./system/database/drivers/cubrid/cubrid_driver.php */